GB1506043A - Gas opacimeters - Google Patents

Abstract

1506043 Gas opacimeter ROBERT BOSCH GmbH 14 May 1975 [28 May 1974 21 March 1975] 20289/75 Heading G1A An opacimeter comprises a burner for burning dirt settled on two discs covering light beam entrance and exit holes 15, 16 in a gas chamber 10. There may be a comparison chamber for pure air with similar holes. In the embodiment of Fig. 2 rotating discs 21, 22 cover the holes of the chamber or chambers. Disc 21 has alternate opaque and transparent sectors. Gas chambers 40, 41 are mounted so that the discs are at the oxidizing regions of flames 42, 43. More burners may be used. When the disc temperature rises gas dirt is not deposited. The speed and directions of gas flow and disc rotation are the same. The temperature is measured by aresistance wire in chamber 10 and kept approximately the same throughout the chamber. In the embodiment of Fig. 3, fixed discs 45, 46 are inserted in and seal holes 15 and 16. Infrared source 47, powered by electricity and with reflective coating 54 is on the axis of the measuring light beam. Mirrors 50, 51, coated with an interference layer so that infrared is transmitted and visible light reflected, deflect the beam from light source 48 and to sensor 53 giving a signal characteristic of gas turbidity. A second infrared source may be disposed opposite opening 16 or instead a lens 55, which may serve instead of disc 45, may focus the infrared beam in the middle of chamber 10 and a mirror 56 may return it. Fuller details of the embodiment of Fig. 2 are described in conjunction with Fig. 1 (not shown).